Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
threatlocker.com
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-21 02:17:19 UTC · ↺ Refresh
MX Hostnames
- threatlocker-com.mail.protection.outlook.com
MX Priorities
- threatlocker-com.mail.protection.outlook.com: 0
A / AAAA Records
- 198.202.211.1 (no PTR)
Mail Server IPs
- 52.101.50.4 ↩ mail-co1pr03cu00404.inbound.protection.outlook.com
- 52.101.9.21 ↩ mail-bl2pr04cu00205.inbound.protection.outlook.com
- 52.101.41.183 ↩ mail-byapr04cu00307.inbound.protection.outlook.com
- 52.101.11.19 ↩ mail-sa9pr04cu00203.inbound.protection.outlook.com
- 2a01:111:f403:f804::2 ↩ mail-co1pr05cu00402.inbound.protection.outlook.com
- 2a01:111:f403:f90d::1 ↩ mail-sn1pr0501cu00301.inbound.protection.outlook.com
- 2a01:111:f403:c901::1 ↩ mail-bl2pr04cu00201.inbound.protection.outlook.com
- 2a01:111:f403:c902::3 ↩ mail-sj0pr03cu01703.inbound.protection.outlook.com
SOA Record
Raw SOA
ns-153.awsdns-19.com awsdns-hostmaster.amazon.com 1 7200 900 1209600 86400
Primary NS (mname)
ns-153.awsdns-19.com
Admin Email (rname)
awsdns-hostmaster@amazon.com
Serial
1
Refresh
7200s
Retry
900s
Expire
1209600s
Minimum TTL
86400s
Nameservers (NS)
ns-153.awsdns-19.com
ns-1706.awsdns-21.co.uk
ns-524.awsdns-01.net
ns-1108.awsdns-10.org
SPF Record
✓ Strict (-all)
v=spf1 ip4:18.226.172.21 include:spf.protection.outlook.com include:docebosaas.com include:3949713.spf04.hubspotemail.net include:sendgrid.net include:cvent-planner.com -all
📊 DNS lookups: 5/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✓ Reject
v=DMARC1; p=reject; rua=mailto:[email protected]; ruf=mailto:[email protected]; sp=reject;
✓ Reject — strongest protection
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
↳ Subdomain policy: reject
DKIM Selectors
✓ 5 found
google._domainkey
selector1._domainkey
selector2._domainkey
s1._domainkey
s2._domainkey
✓ Public key: 216 chars (valid)
✓ DKIM properly configured for selector: google
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
2 records- SPFv=spf1 ip4:18.226.172.21 include:spf.protection.outlook.com include:docebosaas.com include:3949713.spf04.hubspotemail.net include:sendgrid.net include:cvent-planner.com -all
- atlassian-domain-verification=ARPb4rcy7KSqAUpJ2UGs3NfmJiUnCH6fFlG9PtA6G0AYzXKwhPzFe9abZFP5TTMm ~all
Free · No signup required
Add email validation to your forms
Block disposable emails, validate MX records, detect role accounts — unlimited, forever free.
<script src="https://check.verifyswift.com/"></script>
One line of code · Works on any site
See demo & docs
Deep verification
Full email verification for threatlocker.com
SMTP handshake, catch-all detection, custom validation rules, actual deliverability tests, and more.
No credit card required
Get 1,000 Free Credits